Java Programming

Hi - it's the learning student again :) Our new assignment is to create a program to determine leap year, month and day information. So basically you enter a year and the program says if it is a leap year. Then you enter a month and the program determines if that month is part of that leap year. And then you enter a day and determine if that day is part of that leap month that is part of that leap year. I have written a program to determine if it is a leap year and to determine that if the month is february it is a leap month, but not if the month is part of that leap year - so I am missing a step. And so it goes for the leap day - I have created the program to read that the 29th is a leap day but not exculsively to the month of february that falls in the leap year. Make sense? Here is my code so far:

Here are details of the assignment:

1.Prompt the user for a year using GUI dialogue window.
a.Remember to give the user clear direction on input requirements.
i.E.g. "Please enter month as integer 1-12:"

2.Prompt the user for the month using GUI dialogue window.
a.Remember to give the user clear direction on input requirements.
b.** Please note: month must be input as a string, and then converted to an integer for the case statement below. This may require 2 case statements.

3.Prompt the user for a day in the month.
a.This must return a message to the user if the month doesn’t include that day.
b.i.e. entering 30 in a February month should tell the user it is an invalid day and stop execution.

4.Check to see if the year is a leap year.

5.Check to see if the month is a leap month.

6.Check to see if the day is a leap day.

7.Display a user friendly back to the consumer indicating:
a.Year entered & If it is a leap year
b.Month entered & if it is a leap month.
c.The number of days in the month (e.g. January has 31 days, whereas February has 28 unless it is a leap year.
d.The day of the month entered & whether or not is a Leap day.
e.Output can be in three different dialogue windows, or just 1 if desired.

And here is my code - I am not sure what to do next. It is running and compiling without any errors right now but I know I am missing some steps. Any help or advice in what steps to take next would be appreciated!

import javax.swing.JOptionPane;

public class Leap_Year {
	public static void main (String[] args) {
	//Enter a year
	String enterYearString = JOptionPane.showInputDialog("Enter a year: ");
	
	//Convert year to an integer
	int enterYear = Integer.parseInt(enterYearString);
	
	// Check if year is a leap year
		boolean isLeapYear = 
				(enterYear % 4 == 0 && enterYear % 100 != 0) || (enterYear % 400 == 0);
	
	//Enter a month
		String enterMonthString = JOptionPane.showInputDialog("Enter a month as an integer, e.g. 1-12: ");
	
	//Convert month to an integer
	int enterMonth = Integer.parseInt(enterMonthString);	
		
	//Check if month is a leap year
			boolean isLeapMonth = 
					(enterMonth == 2);
			
	//Enter a day
			String enterDayString = JOptionPane.showInputDialog("Enter a Day as an integer, e.g. 1-31: ");
		
	//Convert day to an integer
		int enterDay = Integer.parseInt(enterDayString);	
			
	//Check if day is a leap day
				boolean isLeapDay = 
						(enterDay == 29);		
	
	//Display the result
	String output = "The year " + enterYear + " is a leap year is: " + isLeapYear + 
			"\nThe month " + enterMonth + " is a leap month is: " + isLeapMonth +
			"\nThe day " + enterDay + " is a leap day is: " + isLeapDay;
	JOptionPane.showMessageDialog(null,output);
	}
}